fix: prevent non-combat room repeated rewards during descent (Issue #382)

- Wrap library XP grant in progress < required guard so completed rooms don't grant XP every tick
- Add early return in treasure room tick when progress >= required to skip loot processing
- Initialize non-combat rooms (library, treasure, recovery) during descent in onEnterRoomDescend
- Add regression test file: non-combat-room-reward-guards.test.ts (8 tests)

docs/dependency-graph.json

@@ -1,6 +1,6 @@
 {
   "_meta": {
-    "generated": "2026-06-12T10:30:16.054Z",
+    "generated": "2026-06-12T10:39:14.588Z",
     "description": "Import dependency graph for src/lib/game. Keys are files, values are arrays of files they import.",
     "usage": "To find what a file affects, search for its path in the VALUES. To find what a file depends on, look at its KEY entry."
   },